Encoder connection problems

[Marik]

Hey Folks,

Cannot make the Allin1DC to see the encoders. I followed the manual, which disabled 332, 333, 334, and 335 to value 255. Today finally, I wired the encoders and mapped parameters according to manual 308=1, 309=2, 310=3. I go to PID, but it seems the encoders do not do anything. My guess, some parameters should be changed, but to what?

Thanks, M

[cncsnw]

There are no other parameters that should matter.

You do need to power down, wait, and power back up before any changes you made to Parameters 308-310 take effect.


More likely, you have a hardware problem with the encoders, cables, or connections.

If possible, make or buy a DB9 breakout with test points: something you can plug in in-line with your encoder (between the encoder and the All-in-one unit), which passes all signals through, but which allows you to measure voltages between various points.

You should have 5VDC from pin 9 to pin 2.

Each of the differential signal pins (3, 4, 5, 6, 7 and 8) should be either around 0.5V above pin 2, or around 3.5V above pin 2. The exact values vary with different encoders (different line drivers), but they should be consistent, and in that ballpark.

You should have plus or minus approximately 3VDC across any differential pair: 3 to 6, 4 to 7, or 5 to 8. Again, the exact value varies with encoder. It could be anywhere from 2.5V to 4V. It should either be plus or minus that amount; never 0V.

[Marik]

Thank you for your reply. I used the encoders, which came with the kit from Ajax. I am an electronic engineer and used to wire 24 channel audio mixer consoles, which are by far more complex. I cannot believe I could screw up all three encoders, as I triple checked all the pinouts, etc. In any case, thanks for your suggestions. I will check the voltages tomorrow when I go to the shop.

Best, M

P.S. The 308-310 were with right setting from the factory, so I did not have to change the parameters and power down->up should not make any difference.

[diycncscott]

Marik,

Please create a report using F7-Utilities, Then F7-Report and email the report.zip file to tech@ajaxcnc.com

Are you looking at the PID screen ABS_POS fields for encoder operation or the DRO's?

BTW What is the 7 segment LED in the ALLIN1DC displaying?

[diycncscott]

The DRO won't show any values until the control has been homed.

If the ABS POS fields in the PID screen do not update, you either:

1. Have a problem with the encoders -very unlikely that all your encoders are bad-especially if you purchased them from us as you stated.

2. Have a problem with the encoder inputs. Again, very unlikely that all your encoder inputs are bad.

3. Have a problem with your wiring. I realize you have double checked your wiring but this by far the most likely scenario.

To save you time and money, I'd suggest purchase at least 1 encoder cable from us and use it as a template:

http://www.ajaxcnc.com/ajax-cnc-components $120.00

[Marik]

Thanks for the suggestions! I sorted the problem--my intern put the cables to all encoders themselves upside down, tacking with silicon, so everything was staying in place. Everything works fine.

Jeez! The moral of the story: always check even the simplest and idiot proof task.

Best, M